In organic chemistry tyramine (4-hydroxy-phenethylamine, para-tryamine, p-tyramine) is a monoamine compound derived from the amino acid tyrosine. Tyramine occurs widely in plants and animals and is metabolized by the enzyme monoamine oxidase. In foods, it is often produced by the decarboxylation of tyrosine during fermentation or decay. Foods containing considerable amounts of tyramine include fish, chocolate, alcoholic beverages, and fermented foods such as cheese, soy sauce and soy bean condiments, sauerkraut, and processed meat. In humans, if tyramine metabolism is compromised by the use of monoamine oxidase inhibitors (MAOIs) and foods high in tyramine are ingested, a hypertensive crisis can result.